1. Field of the Invention
The present invention relates generally to bulk material processing and in particular to radiation processing of food and feed materials.
2. Description of the Prior Art
Various materials for human food and animal feed are processed in preparation for consumption. Such material processing can include cleaning, cooking, grinding, mixing, etc. For example, many materials such as grains, vegetable beans, seeds and nuts are cooked to improve their taste, texture, digestability and spoilage resistance. Materials can be steamed, boiled, popped, cracked, etc. in preparation for consumption. In addition to these cooking methods, infrared radiation has also been employed for cooking and for controlling molds, fungi, yeast, spores and bacteria to retard spoilage. The Pierce U.S. Pat. No. 3,694,220; No. 3,701,670 and No. 4,153,733 disclose an infrared radiation cooking method, an infrared micronizing cooker and an infrared radiation cooked wafer respectively.
Both the aforementioned Pierce '220 and '670 patents disclose infrared cooking equipment with tilted plates connected to vibrators for advancing the material in a downhill direction beneath infrared radiators or heaters.
The Newton British Pat. No. 1,379,116 discloses another type of infrared radiation cooking equipment wherein cereals and other seeds are conveyed beneath infrared heaters on an endless woven wire belt. The belt-type infrared radiation processor disclosed in the Newton '116 British patent can be utilized in a method for dehulling cacao beans disclosed in the Zuilichem et al. U. S. Pat. No. 4,322,444.
Infrared radiation processing can benefit a number of food and feed materials. For example, the starches of cereal grains can be gelatinized thereby for improved digestability. Some grains and seeds can be swollen and fractured by infrared radiation for improved texture. Moreover, infrared cooking of some cereal grains and vegetable beans can enhance their flavors, appearances, digestability and nutritional values.
Infrared cooking can also be important for controlling spoilage in processed food and feed materials. For example, untreated oat groats include an enzyme which can cause rancidity or oxidization if not neutralized. Infrared cooking can neutralize these enzymes and thus extend the shelf life of infrared-cooked oat groats in sealed containers to several months. Similar results can be achieved by infrared radiating rice kernels, which are otherwise susceptible to rapid spoilage caused by lipase enzymes. Furthermore, various flours used to bake bread can be infrared cooked to control rope spores which can spoil the finished product.
Heretofore there has not been a bulk material processor or processing method with the advantages and features of the present invention.